The Self-Evaluations Across Life (SELF) Study is a multi-wave longitudinal research project investigating the development and stability of self-evaluations — particularly self-esteem — and related psychological constructs (e.g., narcissism, dispositional envy) across adulthood. The study follows participants over an eight-year period (2013–2021) to capture intra-individual trajectories and inter-individual differences in self-evaluations.